1. Field of the Invention
The present invention relates to an office automation machine such as a printer, a photocopier, or a multi-function machine. More particularly, the present invention relates to a snapfit for fixing a consumable roller such as a pickup roller to a corresponding shaft, facilitating the replacement of the roller, and a roller assembly of an office automation machine having the same.
2. Description of the Related Art
A pickup roller, which is used in an office automation machine such as a printer, a photocopier, and a multi-function machine to pick-up a document paper, is more susceptible to failure due to wear as compared to the other rollers in the same machine. If the pickup roller is worn out, it is required to be replaced with a new one because a worn-out pickup roller has poor contact with the document to be picked up. Due to the poor contact pickup efficiency deteriorates. Accordingly, a pickup roller assembly employed in a general office automation machine has been designed to facilitate the replacement of the worn-out pickup roller.
The pickup roller assembly includes a pickup roller rotatably assembled with a rotary shaft, and a snapfit disposed on the shaft to prevent the pickup roller from disengaging from the shaft. The pickup roller comprises an inner housing and an outer roller portion. Because a part of the shaft hole of the inner housing and a part of the shaft, both formed by D-cut processing, are assembled together, the pickup roller can be rotated together with the shaft.
The snapfit, which is designed to firmly hold the pickup roller to the shaft and facilitate the replacement of the pickup roller, preferably uses an E-ring resiliently fitted into a circular recess formed on an outer circumference of the shaft in a predetermined depth. In addition to the E-ring, a variety of resilient rings having a similar construction to the E-ring, and a ring integrally formed with the housing are currently used.